Oh, that would be my favourite solution! I don't think Orpheus would be willing to forgive a mind flayer that enslaved his mind, considering githyanki history. But I'd like an option to ask Omeluum for help, if you have him as your ally; he seems more powerful in resisting the netherbrain than the emperor anyway.
That and I mean, why would they have Omeluum in the story anyway? He doesn't really tell us anything new, he is just a nice guy to hang around with atm.